The Really Weird Link Between College and Brain Cancer

The Really Weird Link Between College and Brain Cancer

Why you should care

Because you were looking for a reason not to do a doctorate. Or that term paper.

There are some things that we can all agree on. Exercise makes you healthier! School makes you smarter! Yeah … except that it might also result in early death. Consider ditching the old dog-ate-my-homework line in favor of this: “Sorry, teacher. Research shows that learning may be bad for my health.” Bad, as in fatal.

University education may increase the likelihood of brain cancer by 19 percent for men and 23 percent for women.

These are the findings of a Swedish study released in June. More than 4 million Swedes born between 1911 and 1961 were monitored between 1993 and 2010 to see if they developed glioma, the most common of the malignant brain tumors. The results showed that men with university-level education of at least three years were 19 percent more likely to develop glioma. For women, the risk was 23 percent higher. Higher levels of disposable income were associated with 14 percent heightened risk of glioma among men, but not for women. Single men also exhibited significantly lower risk of glioma than married men, but marital status didn’t affect women.

As this study used an observational method, no firm conclusions can be established about the cause and effect beyond association. But the reason for this shocking data may lie in the complexity of the brain. Neurosurgeon Manish Aghi of University of California, San Francisco speculates that a more ”wrapped up” brain — meaning more complex connections between intelligence-related neurons — could give rise to more tumors. “If cancer is like a weed, a high mental status could create risk just as weeds form in rich, fertile soil,” says Aghi.

The actual incidence of illness is less shocking than the study results might initially suggest — and may also render the risk practically negligible. In each group of 3,000 men of the lowest and highest educational levels, the difference is only five as opposed to six diagnoses of glioma. Study co-author Amal Khanolkar of University College London suggests that the higher rate of brain tumor may have an easy — and reassuring — explanation. “The results of the study are primarily because of detection bias,” he says. “More educated people are more likely to realize their symptoms and seek medical care at an earlier stage.” Previous studies corroborate his claim, as the rich often develop smaller tumors. Similarly, higher rates of glioma among married men may be due to their spouses urging them to see doctors more regularly. And Aghi points out that being mentally sharp has obvious benefits: For one thing, more cerebral professions have been associated with reduced levels of Alzheimer’s. Overall, higher socioeconomic status, which is correlated with schooling, also corresponds to slightly longer expected lifespan. “Even if it were true that education causes brain cancer, I’m not going to stop educating myself,” says Aghi.

The next step for Khanolkar and his team of researchers from Sweden is to extend the data set to 2015 and investigate other variables including ethnicity. “We don’t know anything about the etiology of brain tumors,” he says. “We don’t really understand causes beyond ionizing radiation.” So listen to mom and dad and stay in school. Just don’t think too hard.



Numbers and factoids --- fodder for your next cocktail party.